What is Ollama?

Ollama is a free, open-source tool that lets you run large language models (LLMs) locally on your computer with a single command. It handles model downloading, optimization, and provides a simple API—making local AI accessible to anyone.

Quick Answer

Think of Ollama as “Docker for LLMs.” Instead of paying for API access or sending data to the cloud, you run AI models directly on your Mac, Windows, or Linux machine. Your data stays private, there are no usage costs, and it works offline.

How It Works

# Install Ollama
curl -fsSL https://ollama.com/install.sh | sh

# Run a model
ollama run llama3.2

# That's it - you're chatting with AI locally

Key Features

Feature	Description
One-line install	Works on Mac, Windows, Linux
100+ models	Llama, Mistral, Gemma, Phi, CodeLlama, etc.
Automatic optimization	Detects your GPU, optimizes memory
REST API	Compatible with OpenAI API format
Modelfile	Customize models, create variants
Offline capable	No internet needed after download

Supported Models (March 2026)

Model	Parameters	Best For
Llama 4	8B-405B	General purpose
DeepSeek V3.2	67B-671B	Coding, reasoning
Qwen3-Coder	7B-72B	Code generation
Mistral Large 3	123B	Reasoning
Gemma 3	2B-27B	Efficient tasks
Phi-4	14B	Efficient reasoning
CodeLlama	7B-70B	Programming

Hardware Requirements

Model Size	Minimum RAM	Recommended
7B models	8GB	16GB
13B models	16GB	32GB
34B models	32GB	64GB
70B models	64GB	128GB

GPU acceleration: Supported for NVIDIA (CUDA), AMD (ROCm), and Apple Silicon (Metal).

Common Commands

# List available models
ollama list

# Pull a model without running
ollama pull mistral

# Run with a specific prompt
ollama run llama3.2 "Explain quantum computing"

# Start API server
ollama serve

# Create custom model
ollama create my-model -f Modelfile

# Remove a model
ollama rm llama3.2

API Usage

Ollama provides an OpenAI-compatible API:

import requests

response = requests.post('http://localhost:11434/api/generate', json={
    'model': 'llama3.2',
    'prompt': 'What is machine learning?',
    'stream': False
})

print(response.json()['response'])

Or use the OpenAI Python SDK:

from openai import OpenAI

client = OpenAI(
    base_url='http://localhost:11434/v1',
    api_key='ollama'  # Required but not used
)

response = client.chat.completions.create(
    model='llama3.2',
    messages=[{'role': 'user', 'content': 'Hello!'}]
)

Why Use Ollama?

Pros

• ✅ Free forever - No API costs
• ✅ Private - Data never leaves your machine
• ✅ Offline - Works without internet
• ✅ Simple - One command to start
• ✅ Fast - Native GPU acceleration
• ✅ Customizable - Create custom models

Cons

• ❌ Requires decent hardware
• ❌ Local models are smaller than frontier APIs
• ❌ No cloud sync/collaboration
• ❌ You manage updates

Ollama vs Alternatives

Feature	Ollama	LM Studio	vLLM
Ease of use	⭐⭐⭐⭐⭐	⭐⭐⭐⭐⭐	⭐⭐⭐
GUI	❌ (CLI)	✅	❌
Performance	⭐⭐⭐⭐	⭐⭐⭐⭐	⭐⭐⭐⭐⭐
Model variety	⭐⭐⭐⭐⭐	⭐⭐⭐⭐	⭐⭐⭐
API compatibility	⭐⭐⭐⭐⭐	⭐⭐⭐	⭐⭐⭐⭐⭐

Getting Started

1. Install: curl -fsSL https://ollama.com/install.sh | sh
2. Run first model: ollama run llama3.2
3. Chat: Start asking questions
4. Explore: Try different models from ollama.com/library

Related Questions

• How to run LLMs locally
• Ollama vs LM Studio
• Best local LLM tools
• Local LLMs vs API-based

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Last verified: 2026-03-06